document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1122915>Question 1122915</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The side length of a square starts at 0 cm and then begins increasing at a constant rate of 9 cm per second. \r<BR>\n" );
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document.write( "a. Write a formula that expresses the side length of the square in cm, s<BR>\n" );
document.write( ",in terms of the number of seconds t since the square started growing.\r<BR>\n" );
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document.write( "s=\r<BR>\n" );
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document.write( "b Write a formula that expresses the area of the square in cm2, A, in terms of the side length of the square in cm, s.\r<BR>\n" );
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document.write( "A=\r<BR>\n" );
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document.write( "c. Write a formula that expresses the area of the square in cm2, A, in terms of the number of seconds t since the square started growing.\r<BR>\n" );
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document.write( "A=\r<BR>\n" );
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document.write( "d. Suppose the function f determines the area of the square in cm2 given a number of seconds t since the square started growing. Write a function formula for f.\r<BR>\n" );
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document.write( "f(t) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #739100 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=739100\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> s=9t, where t=seconds, and units are cm.<BR>\n" );
document.write( "A=s^2<BR>\n" );
document.write( "A=81t^2\r<BR>\n" );
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document.write( "at 1 second, 81 cm^2<BR>\n" );
document.write( "2--324 cm^2<BR>\n" );
document.write( "3--729 cm^2<BR>\n" );
document.write( "4--1296 cm^2<BR>\n" );
document.write( "f(t)=[9^2(t+1)^2-t^2]<BR>\n" );
document.write( "This is f(t)=81 (2t+1)<BR>\n" );
document.write( "so at 3 seconds  4 seconds will be 81(7) or 567 cm^2, 1296-729. </SPAN>\n" );
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